Apparatus for burning liquid fuel



Nov. 3, 1931 H. F. CLAYTON APPARATUS FOR BURNING LIQUID FUEL Original Filed July 20, 1925 /27 van for 6.29/7] F 6753/07? III Illllllllllll Patented Nov. 3, 1931 UNITED. STATES PATENT OFFICE HARRY r. CLAYTON, or s'rnArHMonnonEBnc, CANADA, Assrsnon, BY ME'sNE AS- smmrnn'rs, ro GEORGE H. woon, or MONTREAL, CANADA APPARATUS .FOR' BURNING LIQUID FUEL Application filed July 20, 1925,'Seria1 No. 44,649, Renewed March 25, 193 1.

fuel'with reasonably high efliciency and without production of free carbon. A further object is to provide an apparatus so simple in its construction and operation that it maybe operated with entire success and safety by 10 even the most unskilledpersons. Another object is to provide an'apparatus of simple,

durable and inexpensive construction, which may be readily installed in existing heating apparatus with substantially no alterations thereto and which will be safe and economical in operation. Various other objects and the advantages of the invention maybe ascertained from the following description.

The device comprises essentially a steam 'generator and superheaterto which a stream of water under pressure is supplied and in which the water is vaporized and the vapor superheated. Associated with the superheater is a. burner of the atomizer or injector 1 type, through which vapor from super-heater is passed as a motive fluid to simultaneously feed the oil andto atomize the same. A hot porous baflie is disposed to beimpinged by the flame from the burner. Air for complete @730 combustion of the fuel issupplied through the baflie.

In the accompanying drawings, which illustrate one form of apparatus such as is suitable for use in a domestic hot water furnace but to the detailsof Which the invention is in no way confined ;e v

' Fig. 1 is a diagrammatic plan view of apparatus suitable for carrying out the process.

Fig. 2 is a diagrammatic elevation of the same.

Referring more particularly to the drawings, 11 designatesa furnaceor combustion chamber, 'thebottom of which is a grate 12 or other structure designed to support a bed of refractories 13 constituting a porous mass above an ash pit or other air channel 14. Doors 15 and 16'respectively are provided for tightly closing the furnace With a view to preventing the entrance of air in appreciable amounts except under control. An air -distributor'17 of any suitable form may be buried in the refractory material 13, themlet of said distributor being "located exteriorly of the furnace and being provided with a valve 18, by means of which the flowc'of air through the distributor may becontrolled. The dlstributor, conveniently, may be a coil having its inlet at the bottom and'its uppermost Jhelix perforated to suitably distribute air to the flame.

A superheater 19 is provided in the furnace above the refractory material and may be in the form of a U-shapedtubularelement, such as illustrated, or may be of other design. Water is supplied to one end of the superheater through a valved pipe 20. Mostcbnv'eniently, the'wate'r supply'is drawn from a stand pipe 21 in which the level is regulated tomaintain a suitable pressurein the pipe 20. 'An. air chamber 22connecting to the lower side of the pipe QOthrough a U-sealmay be provided to avoid pulsations and assist in maintainingasubstantially uniform pressure' in the pipe 20. An adjustable safety valve 23 may-also be provided on the pipe 20.

The opposite endof the superheater is connected by a pipe 24; with a. burner of the atomizer or injector type, designated 25, which is positioned to direct a jet of vapor I or flame emerging'ther'efrom against the refractory'ma terial 13. Liquid fuelis supplied to the injector through a valvedpipe26. The

pipe 26 preferably leads from a-tank in which the level of oil is maintained constant.

The refractory material 13 may be ifirebrick or the like built in a checkerwork'or in such a way as to produce regularly defined passages, or may be merely lumps of broken refractory material ofsuitable size. The es sential thing in regard to the refractory is that it must have high heat capacity and con stltute a layer of suflicient thickness in the furnace. Preferably, the arrangement is as illustrated, that is, the refractory is disposed below the superheater and the flame is directed downwardly against the refractory, so'that the direction of the flame is more or less opposed to the upward movement of air discharged into the furnace from below, for example, through the distributor 17.

ing molecular division.

supplied to support combustion.

The operation is as follows ;Water under pressure is delivered from the pipe 21 and flows through the pipe 20 into the superheater, which is maintained at a temperature sufficiently high for vaporization of water and the superheating of the vapor, that is, in the neighbourhood of 1000 F. or over. The stream of water admitted to the superheater is relatively small and is almost instantly converted to steam, which is highly superheated. The volume of the superheater bears such relation to the volume of water admitted and the volume of vapor (including any gas) emitted that the pressure does not tend to rise unduly, The pressure is also auto matically controlled in that, if it rises above the pressure in the water pipe 21, vapor will tend to blow back into the water and be condensed, thereby reducing the pressure. The pressure in the superheater also tends to hold back the water, so that the supply is to some extent automatically regulated according to the pressure. A fairly even pressure is maintained and pulsations are largely eliminated by the air chamber 22., which may be connected to the pipe 20 through the seal or trap illustrated to prevent loss of water from the bottom of the air column if the vapor should blow back into the water supply pipe 21.

The water vapor, which will obviously be intensely superheated. is delivered to the burner 25 and is used as the motive fluid therein to draw fuel from the tank 27. The fuel is atomized as it emerges from the burn-- er 25 and with suitably constructed apparatus the division will be very fine, approach- This state of fine division is due not so much to pressure as to the high temperature of the atomizing fluid. Under these conditions, the practially gaseous fuel and the oxygen of the vapor may combine. Theoretically, such combination when taking place in presence of the liberated hydrogen would result in the formation of carbon monoxide. The products of any such reaction or of any dissociation of water are to be regarded as included in the term vapor as applied to the fluid emerging from the burner. The stream of vapor leav ing the burner at high temperature, is ignited and the flame directed by the burner against the refractorv material in the furnace. Obviously, sufficient oxygen must be This amount of oxygen is admitted as air at the bottom of the furnace, so that it rises through the hot refractory material and is thereby heated to a temperature at which it will not chill the flame of combustion. The use of an air distributor of some description is advisable for this purpose to effect distribution of the incoming air in the most desirable manner in the furnace, but air may be admitted through the ash pit to rise through the hot refractories. The practical effects observed are the production of a completely transparent, slightly bluish flame which burns entirely without liberation of carbon and which maintains the refractories at a heat varying from bright red to pale-yellow or white, depending upon the relative size of the burner and the mass of refractories and upon the amount of air fuel and water supplied.

The form and arrangement of apparatus illustrated is that suitable for use in domestic heaters, such as hot water or hot air furnaces, or in small industrial installations, but it will be understood that the use of the invention is not thus confined. The U-shaped superheater illustrated has been found most satisfactory for small units, because of the simplicity and inexpensiveness of its construction, its ease of installation and durability, but it will be understood that the invention is not limited to this particular shape of superheater nor to the particular shape anddisposition of the air preheater, nor to the use of safety valves or air cushions. In short, the apparatus shown is capable of all such modifications as lie within the scope of the appended claims.

Having thus described my invention, what I claim is 1. A device of the class described comprising in combination with a furnace, a refractory battle in the lower part thereof, a burner of the atomizer type located above said baflle and adapted to direct a jet of fuel downwardly against the baffle, a heating chamber located above the burner, means to supply oil to the burner, means to supply water under pressure to one end of said chamber, a connection between the other end of said chamber and the burner to supply steam derived from the water to the burner as a motive agent to draw fuel therethrough, and an air preheater located beneath the top of said battle to supply air through the baflle to the furnace, said distributor having a valved inlet.

2. A device of the class described comprising in combination with a furnace including an air inlet below the usual fuel space, a porous refractory baffle occupying the usual fuel space through which air passes upwardly to support combustion in the furnace, an injector type burner disposed to direct a jet of fuel downwardly upon the baffle, a boiler and superheater in the furnace above the bafiie, connections for supplying water under pressure to the boiler and connections between the boiler and burner for supplying superheated steam to the burner, and connections to supply liquid fuel to the burner.

3. A device of the class described, comprising in combination with a furnace including an air inlet below the usual fuel space, an air preheater occupying the usual fuel space of the furnace said preheater comprising a porous mass of refractory material through which air may flow upwardly into the furnace, an injector type burner disposed to direct a jet of fuel downwardly and at an in cline against the preheater whereby fuel will beburned against the preheater to heat the same, a combined boiler and superheater disposed above the preheater and out of the path 1 of the fuel jet from the burner, and connections between the boiler and a water pressure supply and the burner respectively.

4:. In a device of the class described, the combination with a furnace including an air inlet below the usual fuel space of a foraminous refractory baffle occupying the usual fuel space of the furnace through the foramina of which air may enter upwardly, a steam generating and superheating element located above the baflie in a substantially horizontal plane, a fuel atomizer disposed substantially in the plane of the generator and arranged to direct a jet of fuel away from the generator and downwardly onto the baflle, and indi vidual connections to supply water to the generator, to supply steam from the generator to the atomizer and to supply oil to the atomizer.

In witness whereof, I have hereunto set 3 my hand.

HARRY F. CLAYTON. 

